Abstract: In order to study the damage of rock mass under long-term stress which caused by the cracking and propagation of internal cracks in rock mass, the creep crack growth evolution is analyzed by analyzing the creep crack growth and the damage tensor, the crack initiation and propagation of damage tensor and the creep damage evolution of rock mass. The accumulated damage tensor is introduced into the constitutive model, and the model of C++ is compiled to develop a model of the dynamic link library (DLL), which can simulate the creep crack growth. Based on the engineering background of 8106 working face in a coal mine, the model is used to simulate and analyze the damage zone and the stress evolution laws in different periods. The results show that the new constitutive model can be used to analyze the evolution laws of crack growth under creep condition. In the case of creep crack growth, the 90 m wide protective coal pillar can meet the safety requirements.